Parallel radiofrequency (“RF”) coaxial cables are often used to test electronic components, such as memory and logic chips, simultaneously. Such arrays may have a printed circuit board (“PCB”) substrate having numerous coaxial cables permanently soldered to the PCB in a regular pattern. During testing, a robotic arm moves the array into an abutment connection with a mating component and test signals are propagated down each coaxial cable, through the PCB substrate, and into the mating component.
Referring to FIG. 12, an example of a prior art solder connection for a cable array is illustrated. Specifically, to make such a connection, the central conductor 1204 of a coaxial cable 1202 is exposed and inserted with a plug of solder 1203 into a borehole 1205 of a PCB 1201. The connection is heated to reflow the solder and to make the connection permanent. Because of the density of the array and the fact that connection is internal to the borehole, physical inspection of the solder connection tends to be very difficult if not essentially impossible. Consequently, detecting imperfections in the connection is typically performed after the entire array is assembled by measuring its electrical properties.
A typical requirement of coaxial cables arrays is that the cables in the assembly have identical electrical properties. That is, each coaxial cable, each connection, and the entire array should all function together to conform to predetermined specifications. Commonly, each coaxial cable should have the same “electrical length,” which is a measure of the amount of time that a signal takes to propagate along the central conductor wire. Electrical length can vary among coaxial cables, even though the mechanical length is identical.
Because of the permanent nature of soldered connections, if, during manufacture, it is discovered that even one coaxial cable lacks satisfactory electronic performance, then the entire assembly must be discarded. Therefore, undesirable material wastage is a problem with traditional manufacture of parallel arrays of coaxial cables having soldered connections. What is needed, therefore, is a convenient, robust, and reversible method for attaching coaxial cables to a PCB substrate. The present invention fulfills this need among others.